package com.chy.edu.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.chy.edu.mapper.EduCourseMapper;
import com.chy.edu.pojo.EduCourse;
import com.chy.edu.pojo.EduCourseDescription;
import com.chy.edu.pojo.frontvo.CourseFrontVo;
import com.chy.edu.pojo.frontvo.CourseWebVo;
import com.chy.edu.pojo.vo.CourseInfoVo;
import com.chy.edu.pojo.vo.CoursePublishVo;
import com.chy.edu.service.EduChapterService;
import com.chy.edu.service.EduCourseDescriptionService;
import com.chy.edu.service.EduCourseService;
import com.chy.edu.service.EduVideoService;
import com.chy.servicebase.exceptionhandler.GuLiException;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * <p>
 * 课程 服务实现类
 * </p>
 *
 * @author chy
 * @since 2020-10-27
 */
@Service
public class EduCourseServiceImpl extends ServiceImpl<EduCourseMapper, EduCourse> implements EduCourseService {

    // 课程描述注入
    @Autowired
    private EduCourseDescriptionService courseDescriptionService;
    // 注入小节和章节service
    @Autowired
    private EduVideoService videoService;
    @Autowired
    private EduChapterService chapterService;

    // 添加课程基本信息的方法
    @Override
    public String saveCourseInfo(CourseInfoVo courseInfoVo) {
        // 1. 向课程表添加课程基本信息
        // CourseInfoVo对象转换eduCourse对象
        EduCourse eduCourse = new EduCourse();
        BeanUtils.copyProperties(courseInfoVo,eduCourse);
        boolean resultCourseInfo = this.save(eduCourse);
        if (!resultCourseInfo) {
            // 添加失败
            throw new GuLiException(20001,"添加课程信息失败");
        }

        // 获取添加之后课程id
        String cid = eduCourse.getId();

        // 2. 向课程简介表添加课程简介
        EduCourseDescription courseDescription = new EduCourseDescription();
        courseDescription.setDescription(courseInfoVo.getDescription());
        // 设置描述id就是课程id
        courseDescription.setId(cid);
        boolean save = courseDescriptionService.save(courseDescription);
        if (!save) {
            throw new GuLiException(20001, "课程详情信息保存失败");
        }
        return cid;
    }

    // 根据课程ID查询课程基本信息
    @Override
    public CourseInfoVo getCourseId(String courseId) {

        // 1. 查询课程表
        EduCourse eduCourse = baseMapper.selectById(courseId);
        CourseInfoVo courseInfoVo = new CourseInfoVo();
        BeanUtils.copyProperties(eduCourse,courseInfoVo);
        // 2. 查询描述表
        EduCourseDescription courseDescription = courseDescriptionService.getById(courseId);
        courseInfoVo.setDescription(courseDescription.getDescription());

        return courseInfoVo;
    }

    @Override
    public void updateCourseInfo(CourseInfoVo courseInfoVo) {
        // 1. 修改课程表
        EduCourse eduCourse = new EduCourse();
        BeanUtils.copyProperties(courseInfoVo,eduCourse);
        int update = baseMapper.updateById(eduCourse);
        if (update == 0) {
            throw new GuLiException(20001,"修改课程信息失败");
        }

        // 2. 修改描述表
        EduCourseDescription description = new EduCourseDescription();
        description.setId(courseInfoVo.getId());
        description.setDescription(courseInfoVo.getDescription());
        courseDescriptionService.updateById(description);
    }

    // 根据课程id查询课程确认信息
    @Override
    public CoursePublishVo publishCourseInfo(String id) {
        // 调用mapper
        return baseMapper.getPublishCourseInfo(id);
    }

    // 删除课程
    @Override
    public void removeCourse(String courseId) {
        // 1.根据课程id删除小节
        videoService.removeVideoByCourseId(courseId);
        // 2.根据课程id删除章节
        chapterService.removeChapterByCourseId(courseId);
        // 3.根据课程id删除描述
        courseDescriptionService.removeById(courseId);
        // 4. 根据课程id删除课程本身
        int result = baseMapper.deleteById(courseId);
        if (result == 0) { // 失败返回
            throw new GuLiException(20001,"删除失败");
        }
    }

    // 查询前8条热门课程
    @Cacheable(value = "hotCourse",key = "'selectIndexList'")
    @Override
    public List<EduCourse> listHotCourse() {
        QueryWrapper<EduCourse> wrapper = new QueryWrapper<>();
        wrapper.orderByDesc("id");
        wrapper.last("limit 8");
        return baseMapper.selectList(wrapper);
    }

    // 条件带分页查询课程
    @Override
    public Map<String, Object> getCourseFrontList(Page<EduCourse> pageCourse, CourseFrontVo courseFrontVo) {
        QueryWrapper<EduCourse> wrapper = new QueryWrapper<>();
        // 判断条件值是否为空，不为空拼接
        if (!StringUtils.isEmpty(courseFrontVo.getSubjectParentId())) { // 一级分类
            wrapper.eq("subject_parent_id",courseFrontVo.getSubjectParentId());
        }
        if (!StringUtils.isEmpty(courseFrontVo.getSubjectId())) { // 二级分类
            wrapper.eq("subject_id", courseFrontVo.getSubjectId());
        }
        if (!StringUtils.isEmpty(courseFrontVo.getBuyCountSort())) { // 关注度
            wrapper.orderByDesc("buy_count");
        }
        if (!StringUtils.isEmpty(courseFrontVo.getGmtCreateSort())) { // 最新时间
            wrapper.orderByDesc("gmt_create");
        }
        if (!StringUtils.isEmpty(courseFrontVo.getPriceSort())) { // 价格
            wrapper.orderByDesc("price");
        }
        baseMapper.selectPage(pageCourse,wrapper);

        List<EduCourse> items = pageCourse.getRecords();
        long current = pageCourse.getCurrent();
        long pages = pageCourse.getPages();
        long size = pageCourse.getSize();
        long total = pageCourse.getTotal();
        boolean hasNext = pageCourse.hasNext();
        boolean hasPrevious = pageCourse.hasPrevious();

        Map<String, Object> map = new HashMap<>();
        map.put("items", items);
        map.put("current", current);
        map.put("pages", pages);
        map.put("size", size);
        map.put("total", total);
        map.put("hasNext", hasNext);
        map.put("hasPrevious", hasPrevious);

        return map;
    }

    // 根据课程id，编写sql语句查询课程信息
    @Override
    public CourseWebVo getBaseCourseInfo(String courseId) {
        return baseMapper.getBaseCourseInfo(courseId);
    }
}
